In 1972 a group of institutions combined to evaluate adjuvant therapy following definitive surgery in patients with breast cancer with histologically positive axillary nodes. The first protocol compared L-PAM vs a placebo and early results suggested that the L-PAM was superior to placebo treatment. Pre-menopausal women with fewer than 4 positive nodes treated with L-PAM continue to do better six years after the inception of this protocol. When the initial information from this protocol was available, a second one was begun which compared L-PAM alone to L-PAM plus FU. While it is still very early to evaluate the results of this study, it appears that two drugs are superior to one, again in the pre-menopausal group with a small number of positive nodes. The next step-wise protocol was to add methotrexate to the two drugs, to be compared to the two drugs alone. Accrual to this study was completed in the Spring of 1977, and two new protocols were started to replace it, one comparing the two drugs L-PAM and FU with those same drugs plus an immune enhancer, C. parvum, and the second comparing the two drugs alone vs the same drugs plus an antiestrogen, Tamoxifen. Accrual of patients for both of these studies is almost complete, and new adjuvant protocols in Stage II breast cancer will shortly be started. In addition, a Stage I protocol is being written, and the group as a whole is also looking at adjuvant chemotherapy or immunotherapy in colorectal carcinomas. Detailed Progress Reports of the study as a whole have been submitted by the Project Chairman in the Headquarters Office Renewal Application, and a new update of data is expected at the all-group meeting on November 9-10, 1978.